Locomotive draft appliance



7 1,685,574 E. L. SCHELLENS ET AL LOCOMOTIVE DRAFT APPLIANCE Filed May 16, 1925 2 Sheets-Sheet 1 I: [i i? H i I H H 5% I 1 I I y I i I i 1 l I 1 l Sept. 25, 1928.

Sept. 25, 1928. 1,685,574

E. L. SCHELLENS ET AL LOCOMOTIVE DRAFT APPLIANCE Filed May 16, 1925 2 Sheets-Sheet 2 b Wl ATTORNEYS Patented Sept. 25, 1928.

EUGENE L SCI-IELLENS, OF POINTE CLAIRE, QUEBEC,

JR., F LISBON, NEW HAMPSHIRE'ASS CANADA, AND JOEL s. COFFIN, IGNORS, BY MESNE ASSIGNMENTS, TO c-s ENGINEERING COMPANY, A CORPORATION OF DELAWARE.

H LOCO MOTIVE DRAFT APPLIANCE.

Application filed sta is, 1925. Serial No. 30,734.

This invention relates to draft improvements in locomotives, particularly to; those.

using rotary draft creating appliances, such as set forth in our .co-pending application, Serial No. 681,450 filed December 18, 1923. The nature, objects and advantages of our invention will be best understood from the following.

In the operation of locomotives it is often thecase that the throttle is opened too wide for a certain speed and cut-elf with a censequent increase in draft, eventually resulting in opening of the engine pops and a waste of steam and overspeeding the. fan. Also the fact that the standard fixed orifice nozzle employed is a compromise, in that it creates a draft blast whichis an intermediate between the draft required forlow speeds and that required for high speeds, results, under some operating conditions, in blowing the pops.- t

I urthermore when a draft fan is usedto create the draft, such an vappliance as the one above referred to, there is a tendency to blow the pops. r H

The primary object of ourinvention is to overcome'or minimize such wastage oflive steam; and'to overcome over-speeding I lVith the foregoing and such other objects and advantages as will hereinafter appear,

the invention consists in the novel arrangement and combination of parts hereinafter set forth.

In the accompanying drawings illustrating the invention, r

F 1 is a diagrammatic side elevation of a locomotive showing the application of our improvements thereto, certain of the parts being broken away, and

Fig. 2 is an enlarged sectional view of the pressure relieving valve and control mechanism.

Referring now to Fig. 1, the reference character A indicates the locomotive boiler, B the fire box, C the front end or smoke box,

D the draft appliance, E the draft appliancev pressure relieving valve and F the locomotive throttle.

The draft appliance D is supplied with exhaust steam from the locomotive valve chest 7 thru the conduit 8 leading into the fan steam chest 9, which steam constitutes the power medium for rotating the fan 10.

plementary An annular space 11 is fan for the waste products of combustion. from whence they discharge through the dis charge outlet 12.

The fan steam chest. 9 and the annular space or discharge chamber 11 have a connection 13 therebetween provided with a pressure relieving or by-pass valve 14, very similar in construction to an ordinary pop valve. W hen the engine is operating and the live steam pressure approaches the value at which- 4 1 v the ocomotive pops would open, the pressure relieving valve 14 opens, in the manner hereinafter described, whereby fan operating steam is by-passed from the fan chest 9 to the discharge chamber 11, thus reducing the draft created thereby, preventingimdue increase m the steam pressure and preventing opening of the pops and over-speeding the fan.

The valve 14 is also controlled by a suppilot valve 15 consisting of a body 16 in which is slidabl y carried a springpressed follower member 17 pressing'on the button head 18 sion of the follower member spring may be altered by the set screw 20, it being set at a pre-determined pressure to admit steam to the under side of; ing the valve 14. r V

Live'steam is admitted at 22 to the bottom of the plug valve 19by means of the pipe connection 23 leading from the boiler of the plug valve 21 for liftthe locomotive, andwhen the steam admitted reaches a pressure to overcome the tension of the follower spring, the port 25 is uncovered and such steam passes by means of pipe connec ion 26 to the underside of the plunger21.

The by-pass or pressure relieving valve 14 provided around the of a plug valve 19. v The tenhas a downwardly extending stem or spindle 27, the lower end of which carries a piston 28 mounted in the cy inder 29. The piston 28 is normally held in its lower position by means of a spring 30 between it and an adjusting nut 31 by means of which the tension of the spring may be adjusted to any predetermined amount.

Thusit will be seen that when the pressure on the underside of the plunger 21 reaches a point to overcome the tension of the spring 30 the valve 14 will be lifted from its seat to function as previously described, by reason of the stem 27 being in the path of the plunger 21. Condensate accumulates in the cylinder 29550 that thepiston will} normally operate under \vat-er"giving a dash' pot effect. The cavity 32 around the plunger 21 vents to atmosphere to prevent live steam from the pipe 20 from entering the dash;

pot.

lVe claim 1.111 a locomotive, the combination-10f a draft creatin fan 0 )e 'ated b I exhaust steam exhaust steam pressure relieving mean's, and

automatic control means therefor, operating to reduce" the speed of the fan including a steam connection leading from the source of live steam,-sa-idcontrol means being res'p onslve to the pressure of the live steam when t reaches a predetermined value. I

2. In a locomotive, the combination of a draft creating fan-operated by exhaust steam, a. steam chest for the fan; a fan discharge chamber-for the Waste products-of combustion, and-means for by-passin-g some of said operating exhaust: steam from said chest to said cha-mber When the boiler pressure reaches a predetermined value.

3. Ina locomotive, the combination of a draft creating fan operated byexhaust steam and automatic means for icy-passing some of said operating exhaust steamavhen the steam pressure reaches a predetermined value.

4!; In alocomotive, the combinationof a draft creating fan operated by exhaust steam and ha-ving a-s'teain -chest and discharge 1 chamber for the Waste products of-combustion a pop valvecontrolled by-pass connectmg said chest and chamber and automatic control-meansfor said pop "valve including a; steam: CQIHIGCIUOH leading from the source of live steam:

'5.;I-'n a locomot1ve,-the combination of a draft creatingfan operatedb'y exhaust steam" and having a steam chest and a discharge chamber for the Wasteproducts of combus- "ti on'; a pop valve'controlled by-pass connecting sa id chest and chamber and: automatic control means for'said-p0p:valve including a steamconnection leading from the source of vlive steam, together with dash pot means for resistive means maintaining it normally in closed position "but permitting it to open under the influence of the steam When the pressure: thereof" exceeds" a predetermined value, together with means operating to open thevalve upon a rise in-the locomotive-boiler pressure beyond a pred et'ern'iinedp chat.

8. In-con'ibinat-ion with a locomotive steamactuated fan draft mechanism, a relief valve for the fan steam supply having yield-ingly resistive means maintaining it normally in closed position but permitting it =to0pe'nunder the influence of the steam whenthepressure thereof exceeds a predetermined value, together with meansassociated with the valve stem and operat ingto open the valve upon a 1156 in-thelocomotlve boiler pressure beyond a predetermined point.

9; Incombination witha-locomotive steamactuated fa-n' draft mechanism, a relief valve for the fan steam supply having yieldingly resistive means maintaining it normally' inclosed positi'onbut' permitting it-toopenund'er the influence of the steam when the pressure thereof exceeds a predetermined value,

together with means operating to 'open the valve upon a rise inthe: locomotive Iboiler pressure beyond apredeterm ned point, said latter means" including a piston hearing against the valve stem andm'ean's for'delivering live steam thereto;

In testimony" whereof", we have hereunto signed our names.

EUGENE L. scan-minus: J..S. oorrm, JR. s. I 

